Multi-directional dolly transfer system

ABSTRACT

A multiple direction dolly transfer system includes a series of tracks laid out in a grid configuration, and heavy duty dollies capable of transferring heavy loads that roll on the tracks. The tracks are made up of rail sections having a flat section and channel guides. The dollies include metal frames with legs extending downwardly with a ball transfer unit at the foot of each leg. The ball transfer units include a ball housed in a sleeve with ball bearings positioned therein to facilitate the rolling of the dollies. This system is useful for transferring heavy loads within a manufacturing or heavy industrial facility.

1. FIELD OF THE INVENTION

The present invention relates generally to dolly systems typically used in manufacturing plants and other industrial work environments where heavy loads must be transferred from one location to another. More specifically, the present invention includes a track system installed onto the floor of a facility, generally in a grid configuration, and a set of dollies that can be used to bear heavy loads that may be pushed along the tracks.

2. BACKGROUND OF THE INVENTION

Traditionally, in manufacturing plants and other industrial work environments, in order to transfer heavy loads from one location to another, workers have used either large dollies or forklifts. One problem associated with forklifts is that they are expensive pieces of equipment, and can pose substantial safety hazards to workers in a work environment. Traditional dollies are also used for such work, but typically they can bear only limited weight, and are cumbersome for workers to maneuver in industrial work environments. Therefore, it would be desirable to provide a system for transferring heavy loads within a facility that is inexpensive to manufacture and install, and which overcomes some of the shortcomings of prior transfer systems.

3. SUMMARY OF THE INVENTION

The multi-directional dolly transfer system consists of two main components: the track and the dollies. The track is a low-profile metal grid laid out and secured to the floor of a plant or building, in any desired configuration. It includes rail sections of C-channel or flat bar, which run parallel to each other, and may be laid out in a grid formation. The rail sections include channel guides, for guiding the dollies along the track in a certain direction.

The dollies comprise, in a preferred embodiment heavy duty metal frames capable of supporting several thousand pounds of items. The frames are generally rectangular or square shaped, and have crossbar supports. At each corner of each dolly, a leg extends downwardly and includes at the foot a ball transfer unit, which is a ball housed in a sleeve with ball bearings positioned therein to facilitate the rolling of the ball. The ball transfer units provide instant directional change, allowing the dollies to be pushed in any direction without having to orient the wheel in a certain direction. The dollies are placed onto the rail sections, so that the balls are situated within the channel guides of the tracks. Multiple dollies are placed onto the tracks in this manner, and may be pushed (loaded or unloaded) to any point on the track grid.

OBJECTS OF THE INVENTION

Accordingly, an object of the present invention is to provide a new and improved system for transporting heavy materials.

Another object of the present invention is to provide a dolly and track system where the tracks have a low profile with a horizontal flat center for receiving the ball-bearing style wheels of the dollies for transferring heavy loads from one location to another.

Another object of the present invention is to provide a system for transporting heavy materials that is inexpensive to manufacture and install, and which does not require any motorized assistance for workers to move the heavily laden dollies.

Another object of the present invention is to provide a system for transporting heavy materials wherein the tracks may be repositioned with minimal effort.

Other objects and advantages of the invention will become apparent by consideration of the following description of a specific embodiment thereof.

DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a perspective view illustrating a preferred embodiment of the invention.

FIG. 2 is a cross-sectional view of a section of track and one leg of a dolly having a ball transfer unit with the ball positioned on the track, and having L-shaped channel guides along each longitudinal side thereof.

FIG. 3 is a cross-sectional view of an alternate embodiment of a section of track having a radius or incline along the longitudinal sides of the track, and further showing one leg of a dolly having a ball transfer unit with the ball positioned on the track.

FIG. 4 is a cross-sectional view of an alternate embodiment of a section of track having flat low profile channel guides along the longitudinal sides thereof.

DETAILED DESCRIPTION

As shown in FIG. 1, the multi-directional dolly transfer system consists of two main components: the track 10 and the dollies 50. The track 10 comprises a low-profile metal grid laid out and secured to the floor of a plant or building, in any desired parallel configuration. The track includes rail sections 12 of C-channel (not shown) or flat bar 16 forming the base of the channel with attached channel guides 14. In a preferred embodiment, the flat bar portion 16 of the track is a metal strip 3 inches by ⅜ inch, although other suitable sizes may be used. The tracks run parallel to each other, and may be laid out in a grid formation where cross tracks intersect the main tracks. In one embodiment, the channel guides 14 are L-shaped with vertical lips positioned along the longitudinal sides of the rail sections, and are used for maintaining the ball transfer units of the dolly on the track and guiding the dollies along the track in a certain direction, as shown in FIGS. 1 and 2. In a second embodiment, the channel guides 14 are flat bars disposed along a longitudinal edge of the tracks, resulting in a low profile track configuration as shown in FIG. 4.

When utilizing the L-shaped channel guides, each channel guide 14 is positioned so that the vertical portion of the rail section is disposed along an outer longitudinal edge of the rail section. This configuration may be used to ensure that the dollies remain on the tracks, because the flat bar lip on the horizontal portion of the channel guide hinders the ball from coming off of the track, and the vertical lip along the outside longitudinal edges provides an additional measure for keeping the dollies on the tracks, as shown in FIG. 2.

In an alternate embodiment, the tracks may include a radius 20 extending in a downward incline from the top of the channel guides to the floor, which serves as an incline on the longitudinal sides of each rail section, as shown in FIG. 3. This arrangement allows other traditional dollies, carts or forklifts to more easily roll over the tracks, because the wheels of a forklift, for instance, will roll up the incline to the top of the channel guides, and then down the incline on the other side. This arrangement also reduces the likelihood that workers in the plant will trip over the vertical sections of the channel guides.

Alternatively, when using the flat-bar rail channels, the track system is designed to be low profile, having a height from the floor in the range of ½ inch to ¾ inch. In a preferred embodiment, the flat bar rail channels are ¾ inch by ¼ inch strips disposed along the upper longitudinal edges of the flat bar horizontal track portion 16. This arrangement may be preferable in industrial plants where there is a lot of foot traffic around the tracks, or where forklifts or other types of dollies are used and must be maneuvered over the tracks.

In a preferred embodiment, the channel guides are formed from metal, which may be steel, aluminum, or any other suitable material, in either an L-shaped configuration (FIG. 2) or a flat bar channel guide configuration (FIG. 4). In a preferred embodiment, the rail sections are made from cold roll steel. In either the L-shaped channel guide configuration or the flat bar channel guide configuration, each rail section may be formed integrally, or the channel guides 14 may be attached on top of a flat bar 16 along each longitudinal side thereof. The tracks are laid out end to end and secured to a floor of a facility in any suitable manner, including screws, bolts, adhesives or any other attachment means. When the tracks are laid out and secured into a grid formation, the tracks intersect in such a way that the dollies may be moved along the tracks in any desired direction. In a preferred embodiment, the main tracks are laid out in a first direction so that parallel sets of tracks are directly adjacent one another, similar to multiple sets of parallel railroad tracks, as shown in FIG. 1, allowing multiple dollies to be moved in parallel along the first direction. The cross tracks are laid out in a second direction, perpendicular to the first direction, and are spaced apart to correspond with the legs and wheels of the dollies. In this configuration, dollies may be moved in the first direction along the main tracks or in the second direction along the cross tracks, as desired by a user.

The dollies 50, in a preferred embodiment, are heavy duty metal frames 52 capable of supporting items weighing up to several thousand pounds. The frames 52 are generally rectangular or square shaped, and have crossbar supports 54, although other suitable shapes may be used. At each corner of each dolly, a leg 56 extends downwardly and includes at the foot a ball transfer unit 58, which comprises a ball 60 housed in a sleeve 62 with ball bearings (not shown) positioned therein to facilitate the rolling of the ball, as shown in FIG. 2. The ball transfer unit also includes a base plate 66 that is attached to a foot plate 68 on the leg using bolts, screws, or any other suitable attachment means. Optionally, each leg may include support bars 64. In a preferred embodiment, the ball transfer units operate on a recirculating ball principle: as the load moves over the main ball, small balls underneath circulate around a smooth, precision-machined steel table. It is this feature that ensures maximum efficiency, permitting low friction movement in all directions and bearing light or heavy loads from 30 kg (75 lbs) to 2000 kg (4480 lbs), ball transfer units that can accommodate larger loads may be used. Ball transfer units of this type may be purchased from any number of suppliers, including Omnitrack USA, General Bearing Corporation located at 44 High Street, West Nyack, New York 10994. The ball transfer units 58 provide instant directional change, allowing the dollies to be pushed in any direction without having to orient the wheel in a certain direction, which is a common problem associated with castor wheels used heretofore in the prior art.

The dollies 50 are placed onto the rail sections 12, so that the balls 60 within the ball transfer units 58 are situated within the channel guides of the rail sections. The balls 60 are in contact with the flat bar portion 16 of the rail section when the dollies are positioned on the tracks. Multiple dollies may be placed onto the rail sections in this manner, and may be pushed (loaded or unloaded) to any point on the grid. Such a configuration is useful in unloading heavy items such as rolls of textiles or palates of heavy material from a manufacturing assembly line and moving such items to an appropriate inventory or storage facility, until they are loaded onto trucks for distribution to remote locations or customers, for instance.

Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein. All features disclosed in this specification may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. 

1. A multiple direction dolly transfer system comprising a first set of parallel longitudinal tracks comprising a flat horizontal section and channel guides along each longitudinal side thereof; at least one dolly comprising a frame member and at least four leg members extending downwardly from said frame member, each said leg member including a ball transfer unit attached to a bottom portion thereof; wherein said dolly is positioned so that said ball transfer units are disposed on said parallel longitudinal tracks within said channel guides.
 2. The multiple direction dolly transfer system set forth in claim 1, further comprising a second set of parallel longitudinal tracks that intersect said first set of parallel longitudinal tracks in a perpendicular manner, thereby allowing said dolly to be moved along either set of tracks.
 3. The multiple direction dolly transfer system set forth in claim 2, further comprising a third set of parallel longitudinal tracks disposed adjacent to and parallel with said first set of parallel longitudinal tracks, and which intersect said second set of parallel longitudinal tracks in a perpendicular manner, thereby allowing said dolly to be moved along said first, second, or third set of parallel longitudinal tracks.
 4. The multiple direction dolly transfer system set forth in claim 1, wherein said channel guides are integrally formed with said flat horizontal section to form said first set of parallel longitudinal tracks.
 5. The multiple direction dolly transfer system set forth in claim 1, wherein said channel guides are attached to said flat horizontal section to form said first set of parallel longitudinal tracks.
 6. The multiple direction dolly transfer system set forth in claim 1, wherein said channel guides are L-shaped and include vertical lips that are disposed along each longitudinal edge of said flat horizontal section of each said parallel longitudinal track.
 7. The multiple direction dolly transfer system set forth in claim 1, wherein said channel guides are flat-bars disposed along each longitudinal edge of said flat horizontal section of each said parallel longitudinal track
 8. The multiple direction dolly transfer system set forth in claim 1, wherein said first set of parallel longitudinal tracks are formed from multiple rail sections disposed end to end.
 9. The multiple direction dolly transfer system set forth in claim 6, wherein said channel guides further include an incline extending from the top of said vertical lips to a floor on an outer portion of said track.
 10. The multiple direction dolly transfer system set forth in claim 1, wherein said frame member of said dolly is formed into a rectangular shape, and said legs extend from each corner of said frame. 